Federal authorities have charged a 27-year-old Cary man after they say he made an online threat, said non-Muslims had “spit in our faces,” and had an AK-47 and 340 rounds of ammunition, according to a federal prosecutor.

John Stuart Bruce, U.S. Attorney for the Eastern District of North Carolina, announced the arrest Tuesday, but the man was actually arrested Sunday, the same day the post was made.

Garrett Grimsley used the app Whisper to make post Sunday, stating, “Salam, some of you are alright, don’t go to Cary tomorrow,” according to an affidavit filed by a Cary police officer in support of the federal criminal complaint against Grimsley.

The post had a picture of a man with camouflage pants and holding a red flag with a black star in the middle, according to the affidavit.

“For too long the kuffar (non-Muslims) have spit in our faces and trampled our rights,” Grimsley told a cooperating witness in a private message, according to the affidavit. “This cannot continue. I cannot speak of anything. Say your dua (prayers), sleep, and watch the news tomorrow. It will only be the beginning, insha’Allah.”